<template>
  <div>
    <!-- 顶部滑动条区域 -->
    <div id="slider" class="mui-slider">
      <div id="sliderSegmentedControl" class="mui-scroll-wrapper mui-slider-indicator mui-segmented-control mui-segmented-control-inverted">
        <div class="mui-scroll">
          <a  :class="['mui-control-item',
                        item.id==0?'mui-active':'']"
                        v-for="item in cates"
                        :key="item.id"
                        @click="getPhotoListByCateId(item.id)">
                        {{item.title}}
                    </a>
        </div>
      </div>
    </div>
    <!-- 图片列表区域 -->
    <ul class="photo-list">
      <router-link v-for="item in list" :key="item.id" :to="'/home/photoinfo/'+item.id" tag="li">
        <img v-lazy="item.img_url">
        <div class="info"> 
            <h1 class="info-title">{{item.title}}</h1>
            <div class="info-body">{{item.zhaiyao}}</div>
        </div>
      </router-link>
    </ul>
  </div>
</template>
<script>
//导入mui的js文件
import mui from '../../lib/mui/js/mui.min.js'
export default {
  data() {
    return {
      cates: [], //所有分类的列表数组
      list:[] //图片列表的数组
    }
  },
  created() {
    this.getAllCateGory();
    //默认进入页面就主动请求所有图片列表的数据，全部为0
    this.getPhotoListByCateId(0)
  },
  mounted() { //当组件中的dom结构被渲染好并被放到页面中后，会执行这个钩子函数
    //2.初始化滑动控件（需要获取dom，所以在这个mounted钩子函数）
    mui('.mui-scroll-wrapper').scroll({
      deceleration: 0.0005 //flick 减速系数，系数越大，滚动速度越慢，滚动距离越小，默认值0.0006
    });
  },
  methods: {
    getAllCateGory() { //获取所有的图片分类
      this.$http.get('api/getimgcategory').then(result => {
        if (result.body.status === 0) {
          //手动拼接出一个最完整的分类
          result.body.message.unshift({ title: "全部", id: 0 });
          this.cates = result.body.message;
        }
      })
    },
    getPhotoListByCateId(cateId){
        this.$http.get('api/getimages/'+cateId).then(result =>{
            if(result.body.status === 0){
                this.list = result.body.message;
            }
        })
    }
  }
};

</script>
<style scoped>
* {
  touch-action: pan-y;
}
img{
   width:100%; 
   /*解决图片下方像素显示多出的问题*/
   vertical-align: middle;
}
img[lazy=loading] {
  width: 40px;
  height: 300px;
  margin: auto;
}
.photo-list{
    list-style: none;
    margin: 0;
    padding: 10px;
    padding-bottom: 0;
}
li{
    text-align: center;
}
.photo-list li{
    position: relative;
    background-color: #ccc;
    margin-bottom: 10px;
    box-shadow: 0 0 9px #999
}
.info{
    color: white;
    position: absolute;
    bottom: 0;
    background-color: rgba(0,0,0,0.4);
    max-height: 84px;
}
.info-title{
    font-size: 14px;
}
.info-body{
    font-size: 13px;
}
</style>
